Significance of HSPB1 expression in head and neck squamous cell carcinoma: a meta-analysis of published literatures.

OBJECTIVE: HSPB1 functions to prevent stress-induced cellular damage and has is elevated in multiple cancer types. The significance of HSPB1 in HNSCC remains controversial. We sought to perform a meta-analysis of HSPB1 expression to clarify previous findings. STUDY DESIGN: Meta-analysis of all published studies of HSPB1 in HNSCC patients using IHC techniques. METHODS: A literature review was performed on PubMed and Google Scholar search engines using terms HSP27, HSPB1, Heat Shock Proteins, Cancer, Head and Neck Squamous Cell Carcinoma. Additional studies were added by review of manuscript bibliographies. Means and standard deviations for continuous data were obtained for overall HSPB1 expression (in cancer, normal and dysplasia), nodal status and TNM stage. Chi-square and Cochran's Q test were used to test statistical significance. RESULTS: There were 77 studies identified in the context of HSPB1 and cancer in general. Of these, 7 studies (total patients n=347) met inclusion criteria and reported findings in HNSCC using IHC scoring techniques. For the mean difference in HSPB1 expression; cancer vs. normal, cancer vs. dysplasia, and dysplasia vs. normal all showed significance (p<0.0001) however the difference was not homogeneous across studies for cancer vs. dysplasia and normal. The difference was homogeneous for dysplasia vs. normal. There was no significant difference for HSPB1 expression by nodal status or stage. CONCLUSION: HSPB1 is elevated in HNSCC and may be a useful biomarker for this disease.